The invention relates to valved conduits, i.e., pipes including a valve, for regulating and substantially stopping the flow of a fluid through the conduit, and a method of fabricating the valved conduit.
Typical piping systems employ pipes that are joined together at flanges at or near the ends of respective pipe sections. Adjacent pipes are joined together by fastening the flanges, for example, using bolts extending through cooperating bores in the flanges. Valves installed in these piping systems using flanged pipes also typically include flanges or other protrusions that are secured between and to flanges of adjoining pipes to fabricate a valved conduit. Gaskets are frequently employed between the valves and pipes to form seals and prevent leakage of liquids between the flanged pipes and the valve.
Flanged pipes have a variety of drawbacks. For example, since multiple elements must be aligned, i.e., flanges of the pipes flanges of a valve, and gaskets, assembly is complicated. In addition, flange bolts employed to join pipe sections with or without an intervening valve may have sharp edges that can be produced during assembly. These sharp edges and other protrusions are undesirable in many applications, for example, where the joint is exposed and accessible by the public. Furthermore, flange joints are bulky and detract from the overall appearance of a piping system. Flanged joints have an industrial appearance that may be inappropriate in various consumer oriented environments where the joints are exposed.
Accordingly, there is a need for a simple valved conduit that does not require the use of flanged pipes or the alignment of multiple elements in fabrication and that has a pleasing appearance. Likewise, there is a need for a valved conduit that is free of sharp edges or protrusions that might be dangerous to persons who have access to the joints.
The present invention provides a valved conduit and a method of making a valved conduit that is simply fabricated, that has a pleasing appearance to the public, and that is free of sharp edges that might cause injuries.
According to one aspect of the invention, a valved conduit comprises two substantially flangeless pipes that are adhesively bonded end-to-end at respective end walls of the pipe at a joint. A butterfly valve including a protruding stem and a protruding anti-rotation tab is disposed inside the two pipes at the joint. The anti-rotation tab and the stem are engaged by end walls of the pipes at the joint and the stem extends through the joint outside the pipes of the conduit for control of the butterfly valve.
The end walls of two substantially flangeless pipes are shaped to form substantially planar end wall surfaces, each end wall surface also including respective surfaces defining an opening for receiving a valve stem and a slot for receiving a valve anti-rotation tab. An appropriate adhesive is applied to the planar end wall surfaces and the surfaces defining opening and the slot of the two pipes. A butterfly valve including a stem and an anti-rotation tab is positioned within the pipes with the stem and anti-rotation tab received within the openings and the slot, respectively, so that the planar end wall surfaces of the two pipes are in contact with each other and the surfaces of the opening and slot are in contact with the valve stem and the anti-rotation tab. Thereafter, the end wall surfaces of the two pipes are bonded together and to the valve stem and anti-rotation tab.